Plural pushbutton assembly with safety clip interlock means



United States Patent 3,412,221 PLURAL PUSHBUTTON ASSEMBLY WITH SAFETY CLIP INTERLOCK MEANS Anthony A. Di Pilla, Philadelphia, Pa., assignor to Robertshaw Controls Company, Richmond, Va., a corporation of Delaware Filed Feb. 14, 1967, Ser. No. 616,115 8 Claims. (Cl. 200) ABSTRACT OF THE DISCLOSURE A block building assembly, or switchboard, has a plurality of switch pushbuttons, which include pushbuttons which are adjacent to each other and pushbuttons that are unadjacent to each other, such as in rows. Means are provided to prevent the adjacent pushbuttons from being pushed down to actuated positions, so that adjacent pushbuttons cannot be simultaneously in actuated positions, whereas pushbuttons that are unadjacent to each other can be simultaneously in actuated position. This prevents accidental or wrong pushing of adjacent buttons, such as by stradling the space between the buttons with a finger or fingers, as is accidentally likely otherwise to be done.

This invention relates to a pushbutton safety clip for a plural button switch board and the like.

In switch boards or panels that have a plurality of pushbuttons adjacent to each other, such as in rows, such pushbuttons are likely to he accidentally, or wrongly actuated by pushing down adjacent pushbuttons that ordinarily are not intended to be pushed down to simultaneously actuated positions. In these switch panels it is sometimes intended that only pushbuttons that are unadjacent or substantially separated from each other should be pushed down to actuated positions simultaneously. Means are provided by this invention to prevent accidental or wrong pushing down of adjacent buttons while allowing unadjacent or widely separated buttons to be pushed down.

In one embodiment of this invention, one or more safety clips may be used under the pushbuttons, with certain one or more of the pushbuttons having safety clips, and with certain other one or more of the pushbuttons having no safety clips.

Other features of this invention are apparent from this description, the appended claimed subject matter, and the accompanying drawings, in which FIGURE 1 is a diagrammatic plan view of a switch panel having rows of pushbuttons with safety clips provided under certain pushbuttons, in accordance with this invention.

FIGURE 2 is a diagrammatic cross section taken along line 22 of FIGURE 1.

FIGURE 3 is a view of two adjacent pushbuttons being accidentally pushed down simultaneously, with the safety clip operating to stop the movement before actuated position of the switch is reached.

FIGURE 4 is a view showing a safety clip with only two locking prongs.

FIGURE 5 is a view showing a safety clip with four prongs, and with pairs of such prongs in perpendicular relationship.

FIGURE 6 is a view showing a safety clip with three prongs.

FIGURE 7 is a view showing an unthreaded washer to be used where the safety clip is omitted.

Certain words may be used in this specification and in the claimed subject matter that indicate direction, relative position, and the like. Such words are used for the sake of brevity and clearness. However, it is to be understood that such words are used only in connection with the various views in the drawings, and that in actual use, the parts so described may have entirely different direction, relative position and the like. Examples of such words are vertical, horizontal, upper, lower, and the like.

A block building assembly or switch panel 20 may have a plurality of switches 22 which control various electrical elements, not shown. These switches 22 may be the snap switches, which are in one condition, such as an open or unactuated position, when any one of their respective push buttons 1-12 are in their up position, and are in another condition, such as a closed or actuated position, when their respective push buttons 1-12 are pushed down and snapped to their fully actuated positions. Such push but tons, without the safety clip construction of this invention, are well known, and need not further be described.

Each of the switches 22 may have a respective push button shaft receiving bushing 24 which extends upwardly from the switch 22 and passes through a respective opening 26 in the panel 20.

Alternate and unadjacent switches may be provided with the usual annular unthreaded washers 28 which surround the bushings 24 above the panel 20, so that the switches may be securely mounted on the panel by the use of multisided or hexagonal threaded washers or nuts 30. When the threaded nut 30 is tightened, the respective switch 22 is firmly held in mounted position on the panel 20, with its respective push button carried by the switch shaft 32, which extends downwardly through the bushing 24 to actuate the switch 22. Each of the shafts 32 may have respective push button provided thereon which, for convenience in future identification, are differently numbered from 1 to 12 inclusive. However, each of the push buttons may be identical in shape and function, if desired.

The alternate and unadjacent push buttons that are numbered 1, 3, 5, 7, 9, and 11, etc., may be provided with the unthreaded washers 28. Other alternate and unadjacent push buttons are numbered 2, 4, 6, 8, 10 and 12, etc., and are provided with safety clips, such as shown in FIGURES 4, 5 and/or 6, as desired.

All of the safety clips of FIGURES 4-6 may have a central washer or member 34, 36, and 54 respectively.

The clip 38, of FIGURE 4, may have two opposite prongs 40, 40. The prongs 40 may be individually similar to the four prongs shown in FIGURE 5, except that there are only two such prongs in the clip of FIGURE 4.

The clip 42 of FIGURE 5 may be provided with opposite pairs of prongs 44, 44 and 46, 46, which may be similar in function to the prongs 40, 40 of clip 38. The prongs 44, 44 are adapted to interlock adjacent push buttons in the horizontal rows, such as push buttons 1, 2, 3 and 4. The clip 42 may also have oppositely directed prongs 46, 46, which are adapted to interlock adjacent push buttons in vertical rows, such as adjacent push buttons 1, 8 and 9, or 2, 7 and 10, etc. If desired, clips 48, FIGURE 6, may be provided with only three prongs, such as. two opposite prongs 50, 50 and only a single prong 52. The clips 48 may be used along the edges of the panel 20, to prevent prongs from extending out of the edges of the outside buttons, as is shown on the left and bottom edges of FIGURE 1. Clips 48 may be used under buttons 2, 4, 8 and the like.

All of the prongs 40, 44, 46, 50 and 52 may be substantially similar. For convenience, only the prongs 50, which are shown in FIGURES 2 and 3, will be further described, it being understood that such description also applies to all of the other prongs.

The clip 48 may have a central unthreaded washer member 54, which is placed around the bushings 24 of the switches 22 which have the push buttons 2 and 4. The hexagonal threaded nuts 30 are then tightened on the panel or board 20 to secure such switches in place. All of the switches that have clips may be similarly mounted on the switchboard 20. The lower part of the prongs 50, as indicated at 56, FIGURE 3, is relatively resilient in action, by proper tempering, if desired, or by the long leverage which is applied so that it allows the prong 50 to spread outwardly when the respective push button 2 is pushed down. The upper parts or ends 58, 60 and 62 form a relatively rigid hook means or button stopping means or portion, which is made relatively rigid because of the short leverage action involved, or because of special tempering to impart rigidity. These hook parts or ends 58, 60 and 62 are spread outwardly by the lower smaller cylindraceous or hook spreading part 64 of the pushbutton, so that the prongs surrounding any particular pushbutton that has a clip, are spread outwardly to interlock with adjacent pushbuttons and prevent such adjacent pushbuttons from being simultaneously in lower actuated positions with the button with the clip. The hook parts 60 and 62 may include the inner upward hook part 60 and the outer outward hook part 62 forming a joining apex 61 between said parts 60 and 62. These hook parts 60 and 62 and apex 61 cooperate with the pushbuttons and their lower parts 64 to produce the interlocking action shown in FIGURES 2 and 3.

For example, in FIGURE 3, the pushbuttons 2 and 3 have been accidentally pushed down by one or more fingers or the like, and the cylindraceous member 64 of pushbutton 2 has spread out the two hook parts 60, 62 of the two prongs 50. As shown in relation with the pushbutton 3, the cylindraceous part 64 of pushbutton 2 has spread the members 60, 62 and has caused such members to be pushed outwardly so as to be placed under the cylindraceous or hook engaging parts 64 of pushbutton 3 and also of the pushbutton 1, which is not shown in FIG- URE 3, but is shown in FIGURE 1. This locking action between the members 60, 62 and 64 in FIGURE 3 arrests the buttons 2 and 3 and prevents them from being pushed any further down to the actuated positions of the adjacent switches.

The clips of this invention also prevent the adjacent buttons from being later pushed down, after the initial pushbuttons with the clip has been pushed down. This is illustrated in FIGURE 2, where the pushbutton 4 is shown in dotted lines in the fully actuated down position. If the pushbutton 4 is pushed down to the dotted line poistion and remains there by the snap action of the switch, then the prongs 50 are spread to the dotted line position and they will prevent the adjacent pushbuttons 3 and 5 (button 5 is interlocked by the action of prong 52) from being pushed down at a later time. This is caused by the fact that the cylindraceous or hook spreading part 64 of pushbutton 4 pushes the prongs 50 of FIGURE 2, and 52 in FIGURE 1, outwardly so that the cylindraceous hook engaging parts 64 of buttons 3 and 5 will be stopped by the outwardly spread parts, shown in dotted lines in FIGURE 2, to prevent the pushbuttons 3 and 5 from being pushed down to fully actuated position after the pushbuttons 4 has been pushed down to the fully actuated dotted line position.

It may be desired to limit the locking action against adjacent pushbuttons to a single row, which may be either a vertical row or a horizontal row. Under such conditions, then the clip 38, of FIGURE 4, may be used, and this will limit the interlocking action to adjacent pushbuttons of a single row, as is obvious.

Unadjacent pushbuttons are not interlocked, and may be pushed down to actuated positions, without interference from other unadjacent pushbuttons. For example, if pushbutton 4 of FIGURE 1 is pushed down, then unadjacent pushbuttons such as 2, 1, 7, 12, etc., can be pushed down without any interference whatsoever from the downward position of pushbutton 4.

All of the clips herein disclosed may be one piece clips made of sheet metal material, or of plastic material and the like. The central washers 34, 36 and 54 of the clips 38,

42 and 48 may be integral or homogeneous with their respective prongs 40, 44, 46, 50 and 52. Also, if desired, a clip somewhat similar to clip 48, not shown, may be provided for use at the corners of the panel 20. Such clip may have a prong 52 and only one prong 50. For example, at the lower right hand corner of the panel 20, the right hand prong 50 may be omitted so that no prong extends out from under the right side of the pushbutton.

Thus it is to be seen that an improved building block assembly or switch panel and safety clip construction has been provided which prevents accidental and erroneous actuation of adjacent pushbuttons, but which allows the actuation of unadjacent pushbuttons.

While the form of this invention now preferred has been disclosed as required by the statutes, other forms may be used, all coming within the scope of the claimed subject matter.

What is claimed is:

1. In combination: a plurality of push buttons adjacent to and unadjacent from each other, interlocking means to prevent adjacent push buttons from being simultaneously in pushed down actuated positions while permitting unadjacent push buttons to be simultaneously in pushed down actuated positions, and in which said interlocking means includes clip means only under every other push button to limit interlocking action to adjacent push buttons and to prevent interlocking action between unadjacent push buttons.

2. In combination: a plurality of push buttons adjacent to and unadjacent from each other, interlocking means to prevent adjacent push buttons from being simultaneously in pushed down actuated positions while permitting unadjacent push buttons to be simultaneously in pushed down actuated positions, and in which said interlocking means includes clip means under every other push button to limit interlocking action to adjacent push buttons and to prevent interlocking action between unadjacent push buttons, and in which said clip means includes a central washer member under a respective push button, said central washer member having interlocking means which locks :said respective push button and adjacent push buttons when said respective push button is pushed down to actuated position and prevents adjacent push buttons from being pushed down to simultaneous actuated position, and permits unadjacent push buttons to be pushed down to actuated positions.

3. A combination according to claim 2, in which said central washer member has a plurality of upward prongs which are inward a sufficient distance when said respective push button is not in actuated position to permit adjacent push buttons to be pushed to actuated position, and in which said prongs are outward a sufficient dis tance when said respective push button is in actuated position to prevent adjacent push buttons to be pushed to actuated positions.

4. A combination according to claim 3 in which said prongs are relatively flexible adjacent said washer member and have relatively rigid button stopping means adjacent their upper ends.

5. A combination according to claim 4 in which said rigid push button stopping means includes relatively rigid hook means at said upper ends of said prongs.

6. A combination according to claim 5 in which said rigid hook means includes an inner upward hook part and an outer hook part forming a joining apex between said hook parts.

7. In combination: a switch panel, a plurality of switches supported by said panel and having actuating shafts and push buttons at the ends of said shafts, a respective switch of said switches having a safety clip means surrounding its respective actuating shaft, and under its respective push button, said safety clip means having a plurality of upward prongs which are spread outwardly by downward movement of said respective push button, said prongs having push button stopping means at their ends to stop downward movement of the push buttons of said adjacent switches when said respective push button is pushed down.

8. A combination according to claim 7 in which said panel has a plurality of switch receiving openings, and said switches have threaded shaft receiving bushings, said shafts and said bushings extending through said openings with said switches on one side of said panel and said push buttons on the other side of said panel, the respective bushing of said respective switch having said safety clip and a lock nut holding said clip and respective switch against said panel and the adjacent bushings of said adjacent ones of said switches having a washer and a lock nut holding said adjacent switches and washers against said panel.

References Cited UNITED STATES PATENTS 2,831,075 4/1938 Dumke et al 2005 3,221,847 12/1965 Attwood 287-189.36 3,226,493 12/1965 Reimer 200-5 3,325,198 6/1967 Cruse 287189.36

10 LEWIS H. MYERS, Primmy Examiner.

I. R. SCOTT, Assistant Examiner. 

